Diastereo- and Enantioselective Propargylation of Benzofuranones Catalyzed by Pybox-Copper Complex
摘要:
Diastereo- and enantioselective preparation of 2,2-disubstituted benzofuran-3(2H)-one has been realized by a pybox-copper catalyzed reaction between 2-substituted benzofuran-3(2H)-one and propargyl acetate. The utility of this method was demonstrated by further transformation of the terminal alkyne into a methyl ketone without loss of enantiomeric purity.
The intermolecular diastereoselective and enantioselective synthesis of pyrrolo[1,2-a]indoles is developed through a [3+2] cycloaddition between silyl-indole derivatives and α,β-unsaturated N-acyl oxazolidinones by merging photocatalysis and Lewis acid catalysis.
吡咯并[1,2- a ]吲哚的分子间非对映选择性和对映选择性合成是通过甲硅烷基吲哚衍生物与α,β-不饱和N-酰基恶唑烷酮通过光催化和路易斯酸催化的[3 + 2]环加成反应而开发的。
Enantioselective Synthesis of γ-Oxycarbonyl Motifs by Conjugate Addition of Photogenerated α-Alkoxy Radicals
作者:Xiao Dong、Qi Yukki Li、Tehshik P. Yoon
DOI:10.1021/acs.orglett.1c01790
日期:2021.8.6
addition of photogenerated α-alkoxy radicals to acyl pyrazolidinones can be accomplished using a tandem Sc(III) Lewis acid/photoredox catalyst system. Surprisingly, the excited-state oxidation potential was not the only important variable, and the optimal photocatalyst was not the strongest oxidant screened. Our results show that both the oxidation and reduction potentials of the photocatalyst can be
可以使用串联的 Sc(III) Lewis 酸/光氧化还原催化剂体系实现对映选择性催化 Giese 将光生 α-烷氧基自由基加成到酰基吡唑烷酮。令人惊讶的是,激发态氧化电位并不是唯一重要的变量,最佳光催化剂也不是筛选出的最强氧化剂。我们的结果表明,光催化剂的氧化和还原电位对反应结果都很重要,突出了整体考虑在设计光化学反应中的重要性。
Cross-Couplings of Unactivated Secondary Alkyl Halides: Room-Temperature Nickel-Catalyzed Negishi Reactions of Alkyl Bromides and Iodides
作者:Jianrong (Steve) Zhou、Gregory C. Fu
DOI:10.1021/ja0389366
日期:2003.12.1
palladium-catalyzed method for cross-coupling unactivated secondaryalkyl halides has been a long-standing challenge in synthetic chemistry. This communication describes a simple catalyst system-Ni(cod)2/s-Bu-Pybox-that achieves room-temperature Negishi reactions of an array of functionalized primary and secondaryalkylbromides and iodides.
A chiral ruthenium(II)–bis(2-oxazolin-2-yl)pyridine catalyst prepared in situ from optically active bis(2-oxazolin-2-yl)pyridine (Pybox-ip) (2) and [RuCl2(p-cymene)]2 (1) exhibited efficient activity for the asymmetriccyclopropanation (ACP) of styrene and several diazoacetates to give the corresponding trans- and cis-2-phenylcyclopropane-1-carboxylates (3 and 4) in good yields (66—87%). A mixture
Catalytic Amide Activation with Thermally Stable Molybdenum(VI) Dioxide Complexes
作者:Garrett E. Evenson、Wyatt C. Powell、Aaron B. Hinds、Maciej A. Walczak
DOI:10.1021/acs.joc.3c00218
日期:2023.5.5
practical method of oxazoline and thiazoline formation, which can facilitate the synthesis of natural products, chiral ligands, and pharmaceutical intermediates. This method capitalized on a Mo(VI) dioxide catalyst stabilized by substituted picolinic acid ligands, which is tolerant to many functional groups that would otherwise be sensitive to highly electrophilic alternative reagents.